1. Field of the Invention
The present invention relates to a camera having a ranging unit, or an arrangement thereof.
2. Description of the Related Art
In conventional compact cameras, a ranging unit for active AF (automatic focusing) having therein an IRED (infrared ray emitting diode) and a PSD (position sensitive device) is usually used. In these compact cameras, the aperture of their photographing lenses is relatively smaller and the lens barrel unit is relatively shorter than the size of their camera bodies. Therefore, the position where the above-mentioned ranging unit for AF is mounted is hardly limited and this unit can be arranged at an appropriate position on the front of the cameras. It is necessary that a light beam emitted from the front and a light beam which the front receives are not blocked off by a photographer""s hand or the like at the time of ranging.
Conventional electronic cameras in which a CCD, which is an image sensing device whose pixel number is large, is used are high-class cameras suitable for semi-professionals. Therefore, photographing optical systems which have a high zooming ratio and are bright are selected. For this reason, their photographing lens barrel becomes large-sized and long so that the occupation ratio of the photographing lens barrel in the front of the camera body is large and the lens barrel is considerably projected forward from the camera body.
In AF processing of the above-mentioned conventional electronic cameras, a so-called passive contrast AF, as described in the following, has been exclusively used. The position of their focusing lens is changed and then image signals of a subject from their image sensing device are used at every changed position to compare spatial frequencies. In this way, a focusing position is decided.
However, the contrast AF in the above-mentioned conventional electronic cameras is hard to deal with a subject environment having low contrast. That is, in dark places, the contrast therein is greatly lowered; therefore, a contrast peak value, which can cause the lens to be positioned in focus, cannot be detected with sufficient accuracy. Thus, in many cases, the focus of the lens cannot be accurately adjusted. It can be of imagined that in order to compensate for reduced brightness of the subject, an electronic flash bulb for multi-ranging is intermittently set off. However, this manner is impractical.
Even if the brightness of a subject is sufficient, the focus cannot be accurately adjusted in the case that the contrast itself of the subject is insufficient in a focusing area. In the contrast AF at the time of taking a photograph with a high zooming ratio or taking a close-up photograph, an inconvenience that a focusing time becomes long because of a large movement distance of the lens arises.
Incidentally, in the case of conventional electronic cameras into which a ranging unit is integrated wherein a lens barrel is large-sized and long and a camera body does not project at the left hand side of the lens barrel (at the side opposite to a grip), it is difficult that the ranging unit is arranged around the lens barrel of the camera body or at the left side of the camera body.
Furthermore, the lens barrel projects out and the lens barrel is supported by a left hand at the time of taking a photograph; therefore, the space where the ranging unit can be arranged gets smaller in the front of the camera body, as compared with conventional cameras wherein the camera body is held at the left side thereof (as seen from a subject) by a left hand. Thus, it is difficult to arrange the ranging unit.
Hitherto, there have been known no cameras wherein the above-mentioned focusing unit is conveniently arranged in the vicinity of an electronic flash unit.
The present invention has been made in order to overcome the above-mentioned inconveniences. Thus, an object of the present invention is to provide a compact camera making it possible to arrange a ranging unit at an appropriate position of a camera body, for example, even if a lens barrel to be mounted has a large aperture, whereby the camera is easy to handle. Another object of the present invention is to provide a camera which makes it possible to select focusing data from a focusing manner by means of the above-mentioned ranging unit or from another focusing manner and take in the data, and which can be made compact.
An aspect of the camera of the present invention is a camera comprising a photographing lens barrel arranged at one end side of a camera body; a grip portion arranged at the other end side in of the camera body and projecting forward from the camera body; a window for a ranging unit, arranged at the upper side of the front face of the camera body and in the camera body between the grip portion and the photographing lens barrel; and a finger-restricting portion arranged in the camera body below the window for the ranging unit, one end portion of the finger-restricting portion being formed to project from the grip portion toward the photographing lens barrel; wherein this finger-restricting portion restricts positions of user""s fingers when the user grips the front of the grip portion.
Another aspect of the present invention is an electronic camera having an image sensing device for converting a subject image made by the photographing lens barrel photoelectrically, the electronic camera comprising a photographing lens barrel arranged at one end side of a camera body; a grip portion arranged at the other end side of the camera body and projecting forward from the camera body; a window for a ranging unit, arranged at the upper side of the front face of the camera body and in the camera body between the grip portion and the photographing lens barrel; and a finger-restricting portion arranged in the camera body below the window for the ranging unit, one end portion of the finger-restricting portion being formed to project from the grip portion toward the photographing lens barrel; an active type first focusing means disposed correspondingly to the window for the ranging unit; a contrast type second focusing means for outputting focusing signals by use of subject light projected into the image sensing device; and a control means, wherein the control means selects and controls either one of the first focusing means and the second focusing means on the basis of a subject state and a photographing state.
Other features and advantages of the present invention will become clear from the following description.